In recent years, consumer-use video recording equipment, as typified by hard disk recorders, has become widespread. As one application of such video recording equipment, a use mode has been proposed in which videos of visitors during an absence of a user, captured with use of a door intercom camera, are recorded on a consumer-use recorder via a network, and the videos are put to use in preventing crime.
Here, in the case of consumer use, high quality is required of the images that are recorded and played back by the equipment. Even if data that is being recorded is damaged, for example when a power failure or a slippage of a cord from an electrical socket occurs during recording, screen malfunctions, etc. when playing back the data are not allowable.
For this reason, as technology for handling the damage to data, a technology has been disclosed in which, after recording, as consecutive images, a plurality of JPEG images generated by an encoding unit of a digital camera, a bit search is performed for marker bits that exist at a starting point and a termination point of each JPEG, recognizing a position at which an inconsistency has occurred as a damaged portion, and removing the damaged portion from the JPEGs targeted for playback (for example, see Patent Document 1).    Patent Document 1: Japanese Patent No. 3733061